From the Guidelines
The Eustachian tube is a slender passage in the skull, made of bone and cartilage, that connects the back of the nose and middle ear space, behind the eardrum, and plays a crucial role in maintaining ear health by equalizing air pressure, draining fluid and secretions, and protecting the middle ear from secretions and sound pressure. The Eustachian tube serves several important functions, including equalizing air pressure between the middle ear and the outside environment, which is essential for proper hearing and comfort 1. When you experience pressure changes, such as during airplane takeoff or descent, yawning or swallowing activates the Eustachian tube to open briefly, allowing air to flow in or out of the middle ear to balance the pressure. Additionally, the Eustachian tube helps drain fluid and secretions from the middle ear into the throat and protects the middle ear from secretions and sound pressure coming from the nasopharynx.
In children, the Eustachian tube is shorter, wider, and more horizontal than in adults, which is why children are more prone to ear infections 1. Problems with Eustachian tube function can lead to conditions like middle ear infections, ear pain, hearing loss, and feelings of ear fullness or pressure. The anatomy of the immature Eustachian tube in infants has a central role in the susceptibility to infections of the middle ear, and the Eustachian tube epithelium is the frontline defence against the passage and colonization of otopathogens from the nasopharynx 1.
Some key points to note about the Eustachian tube include:
- It connects the middle ear to the back of the throat (nasopharynx) 1
- It equalizes air pressure between the middle ear and the outside environment 1
- It drains fluid and secretions from the middle ear into the throat 1
- It protects the middle ear from secretions and sound pressure coming from the nasopharynx 1
- It is shorter, wider, and more horizontal in children than in adults, making children more prone to ear infections 1
- Problems with Eustachian tube function can lead to conditions like middle ear infections, ear pain, hearing loss, and feelings of ear fullness or pressure 1.
From the Research
Definition and Function of the Eustachian Tube
- The Eustachian tube is a complex structure that connects the middle ear to the nasopharynx, contributing to the normal function of the middle ear 2.
- It plays a crucial role in maintaining the pressure balance between the middle ear and the atmosphere, allowing for proper hearing and ear function.
Eustachian Tube Dysfunction (ETD)
- ETD is thought to contribute to the majority of middle ear pathology, although the mechanisms and degree to which it contributes to middle ear disease are poorly understood 2.
- ETD can be caused by functional obstruction, such as lack of tubal stiffness or an abnormal active opening mechanism, or mechanical obstruction due to extrinsic or intrinsic factors 3.
- Symptoms of ETD include aural fullness and pressure, muffled hearing, tinnitus, and otalgia, and can lead to common ear disorders such as otitis media with effusion, tympanic membrane retraction/perforation, and cholesteatoma 4.
Relationship between Allergy and Eustachian Tube Dysfunction
- The pathophysiology of ETD is thought to be related to functional obstruction and/or nasal cavity and nasopharyngeal inflammation, which can be caused by upper respiratory infections or allergic rhinitis 4.
- Studies have reported an association between allergic rhinitis and ETD, although the current level of evidence is deemed low quality 4.
- Further research is necessary to understand the mechanism behind this positive association and to elucidate the cause of chronic ETD in patients without associated allergies 4.
Clinical Management of Eustachian Tube Dysfunction
- The clinical management of ETD includes medical and surgical treatment options, such as the use of intranasal corticosteroids or oral antihistamines to decrease intranasal inflammation 5, 4.
- Surgical insertion of tympanostomy or ventilation tubes may be necessary to promote drainage of unresolved effusions 6.